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JBLROCKS
04-06-2005, 08:35 PM
I am thinking of building ONE of these as a subwoofer system. I would be using 150-4's as they are designed for a cabinet like this. Any ideas?
Thanks:D

evans224
04-06-2005, 10:22 PM
Find an empty stadium to use it in. I thought my L150's were too big, now I don't feel so bad......

4313B
04-07-2005, 06:38 AM
Any ideas?eBay the 150-4's to a collector and get some real subwoofers (dobermans on u-boats)? :D

Boss96
04-07-2005, 06:53 AM
Just wondering, I see these types of systems used in PA applications. How do you design a cabinet to horn load the woofers? The boxes shown are big but not THAT big, I always thought a horn for low frequencies would have to be huge. Or designs like that shown above really don't go all that low? It would be fun to make a high efficiency system like that.
Bob

arrgh5
04-07-2005, 10:02 AM
The enclosures on your pic look comparable to the classic 4520 horns

http://www.jblpro.com/pub/obsolete/Low_Frequency_Enclosures2.pdf

"...provides maximum loading to 42 hz".

And do not build ONE, build TWO. Think big http://audioheritage.org/vbulletin/images/smilies/biggrin.gif

JBLROCKS
04-07-2005, 09:08 PM
And do not build ONE, build TWO. Think big http://audioheritage.org/vbulletin/images/smilies/biggrin.gif

my house is not THAT big!

Mr. Widget
04-07-2005, 11:33 PM
So are you after a subwoofer or an excuse to build a big ass horn for your pair of 150-4s? If you must use the 150-4s and you want deep bass you would be better off with a large "W" horn. If you want a true sub you would be best served with a modern high excursion woofer designed for true sub woofer applications. The Sub1500 is a fine example from JBL. There are many other excellent choices as well. Like these: http://www.aurasound.com/

Widget

duaneage
04-08-2005, 09:14 PM
Aura is in a class by itself. Up to 3 inches of cone travel, these drivers retail for hundreds of dollars and generate flat response to about 10 Hz.


Call in a building inspector to check your foundation before using these babies.

JBLROCKS
04-09-2005, 08:16 PM
Nice subs Widget:blink: :D

Steve Schell
04-10-2005, 11:54 AM
JBLROCKS, I have to beat the same old drum when it comes to subwoofers. If you are looking for a sub 20 to 80Hz. for a home system, you can't beat a large front loaded horn. What you spend on plywood you will save on drivers. The two sub designs I have built to date both feature a 15Hz. flare rate, 18 to 20 foot path length, and flat response to the mid 20s with 107dB sensitivity. Using a single light cone 15, the sound is very dynamic and clean, with none of the "boom baba boom" resonance of heavy cone subs. Just a thought anyway.

Mr. Widget
04-10-2005, 12:00 PM
Hi Steve, my point was that the horns he was showing will not be true subs. Could you post pics or drawings of your beasts?

Widget

arrgh5
04-10-2005, 12:27 PM
"... and flat response to the mid 20s with 107dB sensitivity..."

Very interesting, Steve. I thought, that this is impossible with only one 15"
horn ?

Steve Schell
04-10-2005, 01:22 PM
Widget, I agree that the double 15 scoop cabinet will not make a very good subwoofer. Due to the radiation from the front and back of the cone cancelling at low frequencies, and the rear loaded horn being too high a flare rate, I would not expect much below 40Hz. from them. These cabinets should have a very punchy midbass.

Arrgh5, the spec of 107dB may indeed be a bit optimistic; it was measured at the mouth of the horn of my original "Big Bottom" design, which exhausts out the side into a nearby corner. Problem with in-room measurements is that any further out and the curve is disturbed greatly by room effects. Most of my photos and drawings are in my old computer at the moment, and have not yet been moved to the new machine. You can see a picture of my second design, the "Big Ed" sub, at the link below. Here on the Enjoy The Music site my partner Rich and I received some coverage of the system we took to the Rocky Mountain Audio Fest. We had a nice big demo room and the sub worked very well in there. I also noticed some tremors outside by the elevators.

http://www.enjoythemusic.com/rockymtn2004/warnke/

arrgh5
04-10-2005, 02:32 PM
http://audioheritage.org/vbulletin/images/smilies/jawdrop.gif Looks incredible. Forgive me my ignorance, please.

Your "Big Ed" seems to be the right sub for JBLROCKS.http://audioheritage.org/vbulletin/images/smilies/biggrin.gif
Love to see more specs and drawings later.http://audioheritage.org/vbulletin/images/smilies/applaud.gif

Zilch
04-10-2005, 07:54 PM
There are now three current threads regarding horn "subwoofers."

An apparent disconnect....

pelly3s
04-10-2005, 08:02 PM
for horn loaded boxes everyone overlooks the eminance lab12, that thing can produce some serious lowend in the right box

Mr. Widget
04-10-2005, 08:05 PM
There are now three current threads regarding horn "subwoofers."

An apparent disconnect....

Should we start another? :applaud:

Widget

Zilch
04-10-2005, 08:26 PM
Should we start another? :applaud:

WidgetNaw,

Let them cut wood. :D

2220B's a subwoofer?

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&category=47095&item=7314760661&rd=1

Oh, O.K., I get it now.... :p